Engine belts & timing belts

It’s no accident for engine belts to have a prominent spot on your car-part replacement calendar. The one or more outside keep components like your alternator and water pump active. Inside, the timing belt (some cars have timing chains) keeps valves from bashing into pistons. When either belt fails, it’s bad news. At the very least, your forward progress will cease to be. At worst, you’ll need major engine work at the mechanic in the case of some timing-belt breakage and the resulting carnage.

When to replace: Every 3 years or 36,000 miles for engine belts or 60,000 to 90,000 miles for the timing belt.